INDICATIONS AND USAGE

Based on published literature, the annual incidence of NAION is 2.5 to 11.8 cases per 100,000 in males aged ≥ 50. An observational case-crossover study evaluated the risk of NAION when PDE5 inhibitor use, as a class, occurred immediately before NAION onset (within 5 half-lives), compared to PDE5 inhibitor use in a prior time period. The results suggest an approximate 2-fold increase in the risk of NAION, with a risk estimate of 2.15 (95% CI 1.06, 4.34). A similar study reported a consistent result, with a risk estimate of 2.27 (95% CI 0.99, 5.20).

Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies.

Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [see Adverse Reactions (6.2)].Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals who have already experienced NAION are at increased risk of NAION recurrence.

5.8 Priapism

Based on published literature, the annual incidence of NAION is 2.5 to 11.8 cases per 100,000 in males aged ≥ 50. An observational case-crossover study evaluated the risk of NAION when PDE5 inhibitor use, as a class, occurred immediately before NAION onset (within 5 half-lives), compared to PDE5 inhibitor use in a prior time period. The results suggest an approximate 2-fold increase in the risk of NAION, with a risk estimate of 2.15 (95% CI 1.06, 4.34). A similar study reported a consistent result, with a risk estimate of 2.27 (95% CI 0.99, 5.20). Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies.

Dosage forms

Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [see Adverse Reactions (6.2)].Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals who have already experienced NAION are at increased risk of NAION recurrence. Therefore, PDE5 inhibitors, including sildenafil sildenafil 20 mg tablets tablets, should be used with caution in these patients and only when the anticipated benefits outweigh the risks. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil tablets, for this uncommon condition.There are no controlled clinical data on the safety or efficacy of sildenafil tablets in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution.5.4 Hearing LossPhysicians should advise patients to stop taking PDE5 inhibitors, including sildenafil tablets, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including sildenafil tablets.

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It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions (6.1, 6.2)].5.5 Hypotension when Co-administered with Alpha-blockers or Anti-hypertensivesAlpha-blockersCaution is advised when PDE5 inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including sildenafil tablets, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects. When vasodilators are used in combination, an additive effect on blood pressure may occur. In some patients, concomitant use of these two drug classes can lower blood pressure significantly[ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting).Consideration should be given to the following:• Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor.In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose [ see Dosage and Administration (2.3)].• In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. Therefore, PDE5 inhibitors, including sildenafil sildenafil 20 mg tablets tablets, should be used with caution in these patients and only when the anticipated benefits outweigh the risks. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including sildenafil tablets, for this uncommon condition.There are no controlled clinical data on the safety or efficacy of sildenafil tablets in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution.5.4 Hearing LossPhysicians should advise patients to stop taking PDE5 inhibitors, including sildenafil tablets, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including sildenafil tablets. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions (6.1, 6.2)].5.5 Hypotension when Co-administered with Alpha-blockers or Anti-hypertensivesAlpha-blockersCaution is advised when PDE5 inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including sildenafil tablets, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects. When vasodilators are used in combination, an additive effect on blood pressure may occur.

In some patients, concomitant use of these two drug classes can lower blood pressure significantly[ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting).Consideration should be given to the following:• Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor.In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose [ see Dosage and Administration (2.3)].• In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor.• Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs.Anti-hypertensivesSildenafil tablets have systemic vasodilatory properties and may further lower blood pressure in patients taking anti-hypertensive medications.In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and sildenafil tablets, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted [see Drug Interactions (7.3)and Clinical Pharmacology (12.2)].5.6 Adverse Reactions with the Concomitant Use of RitonavirThe concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If sildenafil tablets are prescribed to patients taking ritonavir, caution should be used.

• Sildenafil tablets are classified as phosphodiesterase inhibitors.
• White sildenafil tablets are available by prescription only.
• They should not be used with nitrates due to risk of dangerous drops in blood pressure.
• Certain medications may interact with sildenafil, including antibiotics and antifungals.
• The tablets are designed to last approximately 4-6 hours.
• Overuse can lead to adverse effects like dizziness or vision changes.
• Sildenafil helps men with erectile dysfunction achieve and maintain erections.
• The medicine is not an aphrodisiac and requires sexual stimulation.
• The tablets should be stored in a cool, dry place away from children.
• Beware of counterfeit sildenafil tablets sold online.
• Always verify the legitimacy of the medication before use.

Data from subjects exposed to high systemic levels of sildenafil are limited. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200 to 800 mg). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4),Drug Interactions (7.4),and Clinical Pharmacology (12.3) ] .5.7 Combination with other PDE5 Inhibitors or Other Erectile Dysfunction TherapiesThe safety and efficacy of combinations of sildenafil tablets with other PDE5 Inhibitors, including REVATIO or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied.

• Some sildenafil tablets are coated to improve taste and ease swallowing.
• Sildenafil should not be used if allergic to citrate compounds.
• Cost savings on generic sildenafil make it accessible to more users.
• The medication requires no special diet, but avoid fatty foods close to ingestion.
• Sildenafil may cause a modest drop in blood pressure temporarily.
• Do not share prescribed sildenafil with others; it is tailored to individual health.
• Inform your doctor of all medications and health conditions before use.
• Sildenafil may have different effects based on age and health status.
• The medication has been available in various formulations for convenience.
• The effectiveness may vary, and some users might need dose adjustments.
• Always keep sildenafil tablets out of reach of children and pets.

Such combinations may further lower blood pressure. Therefore, the use of such combinations is not recommended.5.8 Effects on BleedingThere have been postmarketing reports of bleeding events in patients who have taken sildenafil tablets. A causal relationship between sildenafil tablets and these events has not been established. In humans, sildenafil tablets have no effect on bleeding time when sildenafil 5mg for sale taken alone or with aspirin.

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If priapism is not treated immediately, penile tissue damage over the counter drugs containing sildenafil and permanent loss of potency could result. Physicians should advise patients to stop use of all phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil tablets, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [see Adverse Reactions (6.2)]. Physicians should advise patients to stop taking PDE5 inhibitors, including sildenafil tablets, and seek prompt medical attention in the event of sudden decrease or loss of hearing. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions (6.1, 6.2)].

Effectiveness by condition:

[ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4),Drug Interactions (7.4),and Clinical Pharmacology (12.3) ] . The safety and efficacy of combinations of sildenafil tablets with other PDE5 Inhibitors, including REVATIO or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied. Therefore, the use of such combinations is not recommended. There have been postmarketing reports of bleeding events in patients who have taken sildenafil tablets.

Clinical monitoring

In addition, the combination of heparin and sildenafil tablets had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans. The use of sildenafil tablets offers no protection against sexually transmitted diseases. 6 ADVERSE REACTIONS The following are discussed in more detail in other sections of the labeling:• Cardiovascular [see Warnings and Precautions(5.1)]• Prolonged Erection and Priapism [see Warnings and Precautions (5.2)]• Effects on the Eye [see Warnings and Precautions(5.3)]• Hearing Loss [ see Warnings and Precautions (5.4)]• Hypotension when Co-administered with Alpha-blockers or Anti-hypertensives [see Warnings and Precautions(5.5)]• Adverse Reactions with the Concomitant Use of Ritonavir [see Warnings and Precautions(5.6)]• Combination with other PDE5 Inhibitors or Other Erectile Dysfunction Therapies [see Warnings and Precautions (5.7)]• Effects on Bleeding [see Warnings and Precautions(5.8)]• Counseling Patients About Sexually Transmitted Diseases [see Warnings and Precautions (5.9)]The most common adverse reactions reported in clinical trials (≥ 2%) are headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, and rash.6.1 Clinical Trials ExperienceBecause clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.Sildenafil tablets were administered to over 3700 patients (aged 19 to 87 years) during pre-marketing clinical trials worldwide. However, in vitrostudies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor).

• Sildenafil tablets are often stored in their original packaging to avoid contamination.
• Use only the amount prescribed; more does not mean better results.
• Sildenafil helps improve erectile function but doesn’t increase libido.
• The tablets are designed for rapid and effective absorption.
• Always inform your doctor about existing health conditions before use.
• Some brands of sildenafil are marketed as "white tablets" for easy recognition.
• The medication can cause a mild increase in blood flow to other body parts.
• Avoid caffeine or heavy meals before taking sildenafil for better results.
• The safety and efficacy of sildenafil are supported by numerous clinical trials.
• Never take expired sildenafil tablets, as their safety can’t be guaranteed.
• Regular blood pressure checks are recommended when using sildenafil long-term.

In addition, the combination of heparin and sildenafil tablets had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans.The safety of sildenafil tablets is unknown in patients with bleeding disorders and patients with active peptic ulceration.5.9 Counseling Patients About Sexually Transmitted DiseasesThe use of sildenafil tablets offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered. There is a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. [ see Clinical Pharmacology (12.2)].While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil tablets, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of sildenafil tablets. If priapism is not treated immediately, penile tissue damage over the counter drugs containing sildenafil and permanent loss of potency could result. Physicians should advise patients to stop use of all phosphodiesterase type 5 (PDE5) inhibitors, including sildenafil tablets, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION [see Adverse Reactions (6.2)]. Physicians should advise patients to stop taking PDE5 inhibitors, including sildenafil tablets, and seek prompt medical attention in the event of sudden decrease or loss of hearing. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors [ see Adverse Reactions (6.1, 6.2)]. [ see Drug Interactions (7.2)and Clinical Pharmacology (12.2)] leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting).

6.2 Post-marketing Experience

To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4),Drug Interactions (7.4),and Clinical Pharmacology (12.3) ] . The safety and efficacy of combinations of sildenafil tablets with other PDE5 Inhibitors, including REVATIO or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied. Therefore, the use of such combinations is not recommended. There have been postmarketing reports of bleeding events in patients who have taken sildenafil tablets. In addition, the combination of heparin and sildenafil tablets had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans.

SC 20

Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor.• Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs.Anti-hypertensivesSildenafil tablets have systemic vasodilatory properties and may further lower blood pressure in patients taking anti-hypertensive medications.In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and sildenafil tablets, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted [see Drug Interactions (7.3)and Clinical Pharmacology (12.2)].5.6 Adverse Reactions with the Concomitant Use of RitonavirThe concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If sildenafil tablets are prescribed to patients taking ritonavir, caution should be used. Data from subjects exposed to high systemic levels of sildenafil are limited. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200 to 800 mg). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended [ see Dosage and Administration (2.4),Drug Interactions (7.4),and Clinical Pharmacology (12.3) ] .5.7 Combination with other PDE5 Inhibitors or Other Erectile Dysfunction TherapiesThe safety and efficacy of combinations of sildenafil tablets with other PDE5 Inhibitors, including REVATIO or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied.

Raynaud's phenomenon

Such combinations may further lower blood pressure. Therefore, the use of such combinations is not recommended.5.8 Effects on BleedingThere have been postmarketing reports of bleeding events in patients who have taken sildenafil tablets. A causal relationship between sildenafil tablets and these events has not been established. In humans, sildenafil tablets have no effect on bleeding time when sildenafil 5mg for sale taken alone or with aspirin. However, in vitrostudies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor).

Sildenafil Citrate

In addition, the combination of heparin and sildenafil tablets had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans.The safety of sildenafil tablets is unknown in patients with bleeding disorders and patients with active peptic ulceration.5.9 Counseling Patients About Sexually Transmitted DiseasesThe use of sildenafil tablets offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered. There is a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. [ see Clinical Pharmacology (12.2)].While this normally would be expected to be of little consequence in most patients, prior to prescribing sildenafil tablets, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of sildenafil tablets. The use of sildenafil tablets offers no protection against sexually transmitted diseases. 6 ADVERSE REACTIONS The following are discussed in more detail in other sections of the labeling:• Cardiovascular [see Warnings and Precautions(5.1)]• Prolonged Erection and Priapism [see Warnings and Precautions (5.2)]• Effects on the Eye [see Warnings and Precautions(5.3)]• Hearing Loss [ see Warnings and Precautions (5.4)]• Hypotension when Co-administered with Alpha-blockers or Anti-hypertensives [see Warnings and Precautions(5.5)]• Adverse Reactions with the Concomitant Use of Ritonavir [see Warnings and Precautions(5.6)]• Combination with other PDE5 Inhibitors or Other Erectile Dysfunction Therapies [see Warnings and Precautions (5.7)]• Effects on Bleeding [see Warnings and Precautions(5.8)]• Counseling Patients About Sexually Transmitted Diseases [see Warnings and Precautions (5.9)]The most common adverse reactions reported in clinical trials (≥ 2%) are headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, and rash.6.1 Clinical Trials ExperienceBecause clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.Sildenafil tablets were administered to over 3700 patients (aged 19 to 87 years) during pre-marketing clinical trials worldwide.

See also: